Ejemplo n.º 1
0
 public void Reset()
 {
     gzipHeaderSubstate             = GzipHeaderState.ReadingID1;
     gzipFooterSubstate             = GzipHeaderState.ReadingCRC;
     expectedCrc32                  = 0;
     expectedOutputStreamSizeModulo = 0;
 }
 public void Reset()
 {
     this.gzipHeaderSubstate       = GzipHeaderState.ReadingID1;
     this.gzipFooterSubstate       = GzipHeaderState.ReadingCRC;
     this.expectedCrc32            = 0;
     this.expectedOutputStreamSize = 0;
 }
Ejemplo n.º 3
0
 public void Reset()
 {
     _gzipHeaderSubstate = GzipHeaderState.ReadingID1;
     _gzipFooterSubstate = GzipHeaderState.ReadingCRC;
     _expectedCrc32 = 0;
     _expectedOutputStreamSizeModulo = 0;
 }
Ejemplo n.º 4
0
        public bool ReadFooter(InputBuffer input)
        {
            input.SkipToByteBoundary();
            if (gzipFooterSubstate == GzipHeaderState.ReadingCRC)
            {
                while (loopCounter < 4)
                {
                    var bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    expectedCrc32 |= (uint)bits << (8 * loopCounter);
                    loopCounter++;
                }
                gzipFooterSubstate = GzipHeaderState.ReadingFileSize;
                loopCounter        = 0;
            }

            if (gzipFooterSubstate == GzipHeaderState.ReadingFileSize)
            {
                if (loopCounter == 0)
                {
                    expectedOutputStreamSizeModulo = 0;
                }

                while (loopCounter < 4)
                {
                    var bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    expectedOutputStreamSizeModulo |= (uint)bits << (8 * loopCounter);
                    loopCounter++;
                }
            }

            return(true);
        }
 public bool ReadFooter(InputBuffer input)
 {
     input.SkipToByteBoundary();
     if (this.gzipFooterSubstate == GzipHeaderState.ReadingCRC)
     {
         while (this.loopCounter < 4)
         {
             int bits = input.GetBits(8);
             if (bits < 0)
             {
                 return(false);
             }
             this.expectedCrc32 |= (uint)(bits << (8 * this.loopCounter));
             this.loopCounter++;
         }
         this.gzipFooterSubstate = GzipHeaderState.ReadingFileSize;
         this.loopCounter        = 0;
     }
     if (this.gzipFooterSubstate == GzipHeaderState.ReadingFileSize)
     {
         if (this.loopCounter == 0)
         {
             this.expectedOutputStreamSize = 0;
         }
         while (this.loopCounter < 4)
         {
             int num2 = input.GetBits(8);
             if (num2 < 0)
             {
                 return(false);
             }
             this.expectedOutputStreamSize |= (uint)(num2 << (8 * this.loopCounter));
             this.loopCounter++;
         }
     }
     return(true);
 }
 public bool ReadFooter(InputBuffer input)
 {
     input.SkipToByteBoundary();
     if (this.gzipFooterSubstate == GzipHeaderState.ReadingCRC)
     {
         while (this.loopCounter < 4)
         {
             int bits = input.GetBits(8);
             if (bits < 0)
             {
                 return false;
             }
             this.expectedCrc32 |= (uint) (bits << (8 * this.loopCounter));
             this.loopCounter++;
         }
         this.gzipFooterSubstate = GzipHeaderState.ReadingFileSize;
         this.loopCounter = 0;
     }
     if (this.gzipFooterSubstate == GzipHeaderState.ReadingFileSize)
     {
         if (this.loopCounter == 0)
         {
             this.expectedOutputStreamSize = 0;
         }
         while (this.loopCounter < 4)
         {
             int num2 = input.GetBits(8);
             if (num2 < 0)
             {
                 return false;
             }
             this.expectedOutputStreamSize |= (uint) (num2 << (8 * this.loopCounter));
             this.loopCounter++;
         }
     }
     return true;
 }
Ejemplo n.º 7
0
        public bool ReadHeader(InputBuffer input) {

            while (true) {
                int bits;
                switch (gzipHeaderSubstate) {
                    case GzipHeaderState.ReadingID1:
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        if (bits != GZipConstants.ID1) {
                            throw new InvalidDataException(SR.GetString(SR.CorruptedGZipHeader));
                        }
                        gzipHeaderSubstate = GzipHeaderState.ReadingID2;
                        goto case GzipHeaderState.ReadingID2;

                    case GzipHeaderState.ReadingID2:
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        if (bits != GZipConstants.ID2) {
                            throw new InvalidDataException(SR.GetString(SR.CorruptedGZipHeader));
                        }

                        gzipHeaderSubstate = GzipHeaderState.ReadingCM;
                        goto case GzipHeaderState.ReadingCM;

                    case GzipHeaderState.ReadingCM:
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        if (bits != GZipConstants.Deflate) {         // compression mode must be 8 (deflate)
                            throw new InvalidDataException(SR.GetString(SR.UnknownCompressionMode));
                        }

                        gzipHeaderSubstate = GzipHeaderState.ReadingFLG; ;
                        goto case GzipHeaderState.ReadingFLG;

                    case GzipHeaderState.ReadingFLG:
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        gzip_header_flag = bits;
                        gzipHeaderSubstate = GzipHeaderState.ReadingMMTime;
                        loopCounter = 0; // 4 MMTIME bytes
                        goto case GzipHeaderState.ReadingMMTime;

                    case GzipHeaderState.ReadingMMTime:
                        bits = 0;
                        while (loopCounter < 4) {
                            bits = input.GetBits(8);
                            if (bits < 0) {
                                return false;
                            }

                            loopCounter++;
                        }

                        gzipHeaderSubstate = GzipHeaderState.ReadingXFL;
                        loopCounter = 0;
                        goto case GzipHeaderState.ReadingXFL;

                    case GzipHeaderState.ReadingXFL:      // ignore XFL
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        gzipHeaderSubstate = GzipHeaderState.ReadingOS;
                        goto case GzipHeaderState.ReadingOS;

                    case GzipHeaderState.ReadingOS:      // ignore OS
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        gzipHeaderSubstate = GzipHeaderState.ReadingXLen1;
                        goto case GzipHeaderState.ReadingXLen1;

                    case GzipHeaderState.ReadingXLen1:
                        if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.ExtraFieldsFlag) == 0) {
                            goto case GzipHeaderState.ReadingFileName;
                        }

                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        gzip_header_xlen = bits;
                        gzipHeaderSubstate = GzipHeaderState.ReadingXLen2;
                        goto case GzipHeaderState.ReadingXLen2;

                    case GzipHeaderState.ReadingXLen2:
                        bits = input.GetBits(8);
                        if (bits < 0) {
                            return false;
                        }

                        gzip_header_xlen |= (bits << 8);
                        gzipHeaderSubstate = GzipHeaderState.ReadingXLenData;
                        loopCounter = 0; // 0 bytes of XLEN data read so far
                        goto case GzipHeaderState.ReadingXLenData;

                    case GzipHeaderState.ReadingXLenData:
                        bits = 0;
                        while (loopCounter < gzip_header_xlen) {
                            bits = input.GetBits(8);
                            if (bits < 0) {
                                return false;
                            }

                            loopCounter++;
                        }
                        gzipHeaderSubstate = GzipHeaderState.ReadingFileName;
                        loopCounter = 0;
                        goto case GzipHeaderState.ReadingFileName;

                    case GzipHeaderState.ReadingFileName:
                        if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.FileNameFlag) == 0) {
                            gzipHeaderSubstate = GzipHeaderState.ReadingComment;
                            goto case GzipHeaderState.ReadingComment;
                        }

                        do {
                            bits = input.GetBits(8);
                            if (bits < 0) {
                                return false;
                            }

                            if (bits == 0) {   // see '\0' in the file name string
                                break;
                            }
                        } while (true);

                        gzipHeaderSubstate = GzipHeaderState.ReadingComment;
                        goto case GzipHeaderState.ReadingComment;

                    case GzipHeaderState.ReadingComment:
                        if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.CommentFlag) == 0) {
                            gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
                            goto case GzipHeaderState.ReadingCRC16Part1;
                        }

                        do {
                            bits = input.GetBits(8);
                            if (bits < 0) {
                                return false;
                            }

                            if (bits == 0) {   // see '\0' in the file name string
                                break;
                            }
                        } while (true);

                        gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
                        goto case GzipHeaderState.ReadingCRC16Part1;

                    case GzipHeaderState.ReadingCRC16Part1:
                        if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.CRCFlag) == 0) {
                            gzipHeaderSubstate = GzipHeaderState.Done;
                            goto case GzipHeaderState.Done;
                        }

                        bits = input.GetBits(8);     // ignore crc
                        if (bits < 0) {
                            return false;
                        }

                        gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part2;
                        goto case GzipHeaderState.ReadingCRC16Part2;

                    case GzipHeaderState.ReadingCRC16Part2:
                        bits = input.GetBits(8);     // ignore crc
                        if (bits < 0) {
                            return false;
                        }

                        gzipHeaderSubstate = GzipHeaderState.Done;
                        goto case GzipHeaderState.Done;

                    case GzipHeaderState.Done:
                        return true;
                    default:
                        Debug.Assert(false, "We should not reach unknown state!");
                        throw new InvalidDataException(SR.GetString(SR.UnknownState));
                }
            }
        }
Ejemplo n.º 8
0
        public bool ReadFooter(InputBuffer input) {
            input.SkipToByteBoundary();
            if (gzipFooterSubstate == GzipHeaderState.ReadingCRC) {
                while (loopCounter < 4) { 
                    int bits = input.GetBits(8);
                    if (bits < 0) {
                        return false;
                    }

                    expectedCrc32 |= ((uint)bits << (8 * loopCounter));
                    loopCounter++;
                }
                gzipFooterSubstate = GzipHeaderState.ReadingFileSize;
                loopCounter = 0;

            }

            if (gzipFooterSubstate == GzipHeaderState.ReadingFileSize) {
                if (loopCounter == 0)
                    expectedOutputStreamSizeModulo = 0;

                while (loopCounter < 4) {
                    int bits = input.GetBits(8);
                    if (bits < 0) {
                        return false;
                    }

                    expectedOutputStreamSizeModulo |= ((uint) bits << (8 * loopCounter));
                    loopCounter++;
                }
            }

            return true;
        }
Ejemplo n.º 9
0
        public bool ReadHeader(InputBuffer input)
        {
            while (true)
            {
                int bits;
                switch (gzipHeaderSubstate)
                {
                case GzipHeaderState.ReadingID1:
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    if (bits != GZipConstants.ID1)
                    {
                        throw new InvalidDataException(SR.GetString(SR.CorruptedGZipHeader));
                    }
                    gzipHeaderSubstate = GzipHeaderState.ReadingID2;
                    goto case GzipHeaderState.ReadingID2;

                case GzipHeaderState.ReadingID2:
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    if (bits != GZipConstants.ID2)
                    {
                        throw new InvalidDataException(SR.GetString(SR.CorruptedGZipHeader));
                    }

                    gzipHeaderSubstate = GzipHeaderState.ReadingCM;
                    goto case GzipHeaderState.ReadingCM;

                case GzipHeaderState.ReadingCM:
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    if (bits != GZipConstants.Deflate)
                    {
                        throw new InvalidDataException(SR.GetString(SR.UnknownCompressionMode));
                    }

                    gzipHeaderSubstate = GzipHeaderState.ReadingFLG;
                    ;
                    goto case GzipHeaderState.ReadingFLG;

                case GzipHeaderState.ReadingFLG:
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzip_header_flag   = bits;
                    gzipHeaderSubstate = GzipHeaderState.ReadingMMTime;
                    loopCounter        = 0;                      // 4 MMTIME bytes
                    goto case GzipHeaderState.ReadingMMTime;

                case GzipHeaderState.ReadingMMTime:
                    bits = 0;
                    while (loopCounter < 4)
                    {
                        bits = input.GetBits(8);
                        if (bits < 0)
                        {
                            return(false);
                        }

                        loopCounter++;
                    }

                    gzipHeaderSubstate = GzipHeaderState.ReadingXFL;
                    loopCounter        = 0;
                    goto case GzipHeaderState.ReadingXFL;

                case GzipHeaderState.ReadingXFL:                         // ignore XFL
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzipHeaderSubstate = GzipHeaderState.ReadingOS;
                    goto case GzipHeaderState.ReadingOS;

                case GzipHeaderState.ReadingOS:                         // ignore OS
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzipHeaderSubstate = GzipHeaderState.ReadingXLen1;
                    goto case GzipHeaderState.ReadingXLen1;

                case GzipHeaderState.ReadingXLen1:
                    if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.ExtraFieldsFlag) == 0)
                    {
                        goto case GzipHeaderState.ReadingFileName;
                    }

                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzip_header_xlen   = bits;
                    gzipHeaderSubstate = GzipHeaderState.ReadingXLen2;
                    goto case GzipHeaderState.ReadingXLen2;

                case GzipHeaderState.ReadingXLen2:
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzip_header_xlen  |= bits << 8;
                    gzipHeaderSubstate = GzipHeaderState.ReadingXLenData;
                    loopCounter        = 0;                      // 0 bytes of XLEN data read so far
                    goto case GzipHeaderState.ReadingXLenData;

                case GzipHeaderState.ReadingXLenData:
                    bits = 0;
                    while (loopCounter < gzip_header_xlen)
                    {
                        bits = input.GetBits(8);
                        if (bits < 0)
                        {
                            return(false);
                        }

                        loopCounter++;
                    }
                    gzipHeaderSubstate = GzipHeaderState.ReadingFileName;
                    loopCounter        = 0;
                    goto case GzipHeaderState.ReadingFileName;

                case GzipHeaderState.ReadingFileName:
                    if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.FileNameFlag) == 0)
                    {
                        gzipHeaderSubstate = GzipHeaderState.ReadingComment;
                        goto case GzipHeaderState.ReadingComment;
                    }

                    do
                    {
                        bits = input.GetBits(8);
                        if (bits < 0)
                        {
                            return(false);
                        }

                        if (bits == 0)
                        {
                            break;
                        }
                    } while (true);

                    gzipHeaderSubstate = GzipHeaderState.ReadingComment;
                    goto case GzipHeaderState.ReadingComment;

                case GzipHeaderState.ReadingComment:
                    if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.CommentFlag) == 0)
                    {
                        gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
                        goto case GzipHeaderState.ReadingCRC16Part1;
                    }

                    do
                    {
                        bits = input.GetBits(8);
                        if (bits < 0)
                        {
                            return(false);
                        }

                        if (bits == 0)
                        {
                            break;
                        }
                    } while (true);

                    gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
                    goto case GzipHeaderState.ReadingCRC16Part1;

                case GzipHeaderState.ReadingCRC16Part1:
                    if ((gzip_header_flag & (int)GZipOptionalHeaderFlags.CRCFlag) == 0)
                    {
                        gzipHeaderSubstate = GzipHeaderState.Done;
                        goto case GzipHeaderState.Done;
                    }

                    bits = input.GetBits(8);                             // ignore crc
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part2;
                    goto case GzipHeaderState.ReadingCRC16Part2;

                case GzipHeaderState.ReadingCRC16Part2:
                    bits = input.GetBits(8);                             // ignore crc
                    if (bits < 0)
                    {
                        return(false);
                    }

                    gzipHeaderSubstate = GzipHeaderState.Done;
                    goto case GzipHeaderState.Done;

                case GzipHeaderState.Done:
                    return(true);

                default:
                    Debug.Assert(false, "We should not reach unknown state!");
                    throw new InvalidDataException(SR.GetString(SR.UnknownState));
                }
            }
        }
        public bool ReadHeader(InputBuffer input)
        {
            int bits;

            switch (this.gzipHeaderSubstate)
            {
            case GzipHeaderState.ReadingID1:
                bits = input.GetBits(8);
                if (bits >= 0)
                {
                    if (bits != 0x1f)
                    {
                        throw new InvalidDataException(SR.GetString("CorruptedGZipHeader"));
                    }
                    this.gzipHeaderSubstate = GzipHeaderState.ReadingID2;
                    break;
                }
                return(false);

            case GzipHeaderState.ReadingID2:
                break;

            case GzipHeaderState.ReadingCM:
                goto Label_00A5;

            case GzipHeaderState.ReadingFLG:
                goto Label_00CE;

            case GzipHeaderState.ReadingMMTime:
                goto Label_00F1;

            case GzipHeaderState.ReadingXFL:
                goto Label_0128;

            case GzipHeaderState.ReadingOS:
                goto Label_013D;

            case GzipHeaderState.ReadingXLen1:
                goto Label_0152;

            case GzipHeaderState.ReadingXLen2:
                goto Label_017B;

            case GzipHeaderState.ReadingXLenData:
                goto Label_01A8;

            case GzipHeaderState.ReadingFileName:
                goto Label_01E5;

            case GzipHeaderState.ReadingComment:
                goto Label_0212;

            case GzipHeaderState.ReadingCRC16Part1:
                goto Label_0240;

            case GzipHeaderState.ReadingCRC16Part2:
                goto Label_026A;

            case GzipHeaderState.Done:
                goto Label_0280;

            default:
                throw new InvalidDataException(SR.GetString("UnknownState"));
            }
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return(false);
            }
            if (bits != 0x8b)
            {
                throw new InvalidDataException(SR.GetString("CorruptedGZipHeader"));
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingCM;
Label_00A5:
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return(false);
            }
            if (bits != 8)
            {
                throw new InvalidDataException(SR.GetString("UnknownCompressionMode"));
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingFLG;
Label_00CE:
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return(false);
            }
            this.gzip_header_flag   = bits;
            this.gzipHeaderSubstate = GzipHeaderState.ReadingMMTime;
            this.loopCounter        = 0;
Label_00F1:
            bits = 0;
            while (this.loopCounter < 4)
            {
                if (input.GetBits(8) < 0)
                {
                    return(false);
                }
                this.loopCounter++;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXFL;
            this.loopCounter        = 0;
Label_0128:
            if (input.GetBits(8) < 0)
            {
                return(false);
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingOS;
Label_013D:
            if (input.GetBits(8) < 0)
            {
                return(false);
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXLen1;
Label_0152:
            if ((this.gzip_header_flag & 4) == 0)
            {
                goto Label_01E5;
            }
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return(false);
            }
            this.gzip_header_xlen   = bits;
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXLen2;
Label_017B:
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return(false);
            }
            this.gzip_header_xlen  |= bits << 8;
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXLenData;
            this.loopCounter        = 0;
Label_01A8:
            bits = 0;
            while (this.loopCounter < this.gzip_header_xlen)
            {
                if (input.GetBits(8) < 0)
                {
                    return(false);
                }
                this.loopCounter++;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingFileName;
            this.loopCounter        = 0;
Label_01E5:
            if ((this.gzip_header_flag & 8) == 0)
            {
                this.gzipHeaderSubstate = GzipHeaderState.ReadingComment;
            }
            else
            {
                do
                {
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }
                }while (bits != 0);
                this.gzipHeaderSubstate = GzipHeaderState.ReadingComment;
            }
Label_0212:
            if ((this.gzip_header_flag & 0x10) == 0)
            {
                this.gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
            }
            else
            {
                do
                {
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return(false);
                    }
                }while (bits != 0);
                this.gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
            }
Label_0240:
            if ((this.gzip_header_flag & 2) == 0)
            {
                this.gzipHeaderSubstate = GzipHeaderState.Done;
                goto Label_0280;
            }
            if (input.GetBits(8) < 0)
            {
                return(false);
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part2;
Label_026A:
            if (input.GetBits(8) < 0)
            {
                return(false);
            }
            this.gzipHeaderSubstate = GzipHeaderState.Done;
Label_0280:
            return(true);
        }
        public bool ReadHeader(InputBuffer input)
        {
            int bits;
            switch (this.gzipHeaderSubstate)
            {
                case GzipHeaderState.ReadingID1:
                    bits = input.GetBits(8);
                    if (bits >= 0)
                    {
                        if (bits != 0x1f)
                        {
                            throw new InvalidDataException(SR.GetString("CorruptedGZipHeader"));
                        }
                        this.gzipHeaderSubstate = GzipHeaderState.ReadingID2;
                        break;
                    }
                    return false;

                case GzipHeaderState.ReadingID2:
                    break;

                case GzipHeaderState.ReadingCM:
                    goto Label_00A5;

                case GzipHeaderState.ReadingFLG:
                    goto Label_00CE;

                case GzipHeaderState.ReadingMMTime:
                    goto Label_00F1;

                case GzipHeaderState.ReadingXFL:
                    goto Label_0128;

                case GzipHeaderState.ReadingOS:
                    goto Label_013D;

                case GzipHeaderState.ReadingXLen1:
                    goto Label_0152;

                case GzipHeaderState.ReadingXLen2:
                    goto Label_017B;

                case GzipHeaderState.ReadingXLenData:
                    goto Label_01A8;

                case GzipHeaderState.ReadingFileName:
                    goto Label_01E5;

                case GzipHeaderState.ReadingComment:
                    goto Label_0212;

                case GzipHeaderState.ReadingCRC16Part1:
                    goto Label_0240;

                case GzipHeaderState.ReadingCRC16Part2:
                    goto Label_026A;

                case GzipHeaderState.Done:
                    goto Label_0280;

                default:
                    throw new InvalidDataException(SR.GetString("UnknownState"));
            }
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return false;
            }
            if (bits != 0x8b)
            {
                throw new InvalidDataException(SR.GetString("CorruptedGZipHeader"));
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingCM;
        Label_00A5:
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return false;
            }
            if (bits != 8)
            {
                throw new InvalidDataException(SR.GetString("UnknownCompressionMode"));
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingFLG;
        Label_00CE:
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return false;
            }
            this.gzip_header_flag = bits;
            this.gzipHeaderSubstate = GzipHeaderState.ReadingMMTime;
            this.loopCounter = 0;
        Label_00F1:
            bits = 0;
            while (this.loopCounter < 4)
            {
                if (input.GetBits(8) < 0)
                {
                    return false;
                }
                this.loopCounter++;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXFL;
            this.loopCounter = 0;
        Label_0128:
            if (input.GetBits(8) < 0)
            {
                return false;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingOS;
        Label_013D:
            if (input.GetBits(8) < 0)
            {
                return false;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXLen1;
        Label_0152:
            if ((this.gzip_header_flag & 4) == 0)
            {
                goto Label_01E5;
            }
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return false;
            }
            this.gzip_header_xlen = bits;
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXLen2;
        Label_017B:
            bits = input.GetBits(8);
            if (bits < 0)
            {
                return false;
            }
            this.gzip_header_xlen |= bits << 8;
            this.gzipHeaderSubstate = GzipHeaderState.ReadingXLenData;
            this.loopCounter = 0;
        Label_01A8:
            bits = 0;
            while (this.loopCounter < this.gzip_header_xlen)
            {
                if (input.GetBits(8) < 0)
                {
                    return false;
                }
                this.loopCounter++;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingFileName;
            this.loopCounter = 0;
        Label_01E5:
            if ((this.gzip_header_flag & 8) == 0)
            {
                this.gzipHeaderSubstate = GzipHeaderState.ReadingComment;
            }
            else
            {
                do
                {
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return false;
                    }
                }
                while (bits != 0);
                this.gzipHeaderSubstate = GzipHeaderState.ReadingComment;
            }
        Label_0212:
            if ((this.gzip_header_flag & 0x10) == 0)
            {
                this.gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
            }
            else
            {
                do
                {
                    bits = input.GetBits(8);
                    if (bits < 0)
                    {
                        return false;
                    }
                }
                while (bits != 0);
                this.gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part1;
            }
        Label_0240:
            if ((this.gzip_header_flag & 2) == 0)
            {
                this.gzipHeaderSubstate = GzipHeaderState.Done;
                goto Label_0280;
            }
            if (input.GetBits(8) < 0)
            {
                return false;
            }
            this.gzipHeaderSubstate = GzipHeaderState.ReadingCRC16Part2;
        Label_026A:
            if (input.GetBits(8) < 0)
            {
                return false;
            }
            this.gzipHeaderSubstate = GzipHeaderState.Done;
        Label_0280:
            return true;
        }
 public void Reset()
 {
     this.gzipHeaderSubstate = GzipHeaderState.ReadingID1;
     this.gzipFooterSubstate = GzipHeaderState.ReadingCRC;
     this.expectedCrc32 = 0;
     this.expectedOutputStreamSize = 0;
 }